<!DOCTYPE html>
<html>
<head>
	<meta charset="utf-8">
    <meta name="viewport" content="width=device-width">
    <title>myplugin1</title>
</head>
<body>
	
    <div class='app'>app1</div>
    <div class='app'>app2</div>
    <div>app3</div>
    <p>app4</p>
</body>
<script src='./index.js'></script>
<script type="text/javascript">

    const app = new MyPlugin('.app')
    const p = new MyPlugin('p')

    app.setBgColor('#f00').setfontSize('30px')
    p.setBgColor()

</script>
</html>